Lee commenced his retreat in the direction of the Potomac on the night of the 4th of July. That the movement did not begin earlier is the best proof of the continued efficiency of his army and his own willingness to accept battle if the enemy were inclined to offer it.
After the failure of the attack on the Federal centre, he had withdrawn Ewell from his position southeast of Gettysburg, and, forming a continuous line of battle on Seminary Ridge, awaited the anticipated assault of General Meade. What the result of such an assault would have been it is impossible to say, but the theory that an attack would have terminated in the certain rout of the Southern army has nothing whatever to support it. The morale of Lee's army was untouched. The men, instead of being discouraged by the tremendous conflicts of the preceding days, were irate, defiant, and ready to resume the struggle. Foreign officers, present at the time, testify fully upon this point, describing the demeanor of the troops as all that could be desired in soldiers; and General Longstreet afterward stated that, with his two divisions under Hood and McLaws, and his powerful artillery, he was confident, had the enemy attacked, of inflicting upon them a blow as heavy as that which they had inflicted upon Pickett. The testimony of General Meade himself fully corroborates these statements. When giving his evidence afterward before the war committee, he said:
"My opinion is, now, that General Lee evacuated that position, not from the fear that he would be dislodged from it by any active operations on my part, but that he was fearful that a force would be sent to Harper's Ferry to cut off his communications…. That was what caused him to retire."
When asked the question, "Did you discover, after the battle of
Gettysburg, any symptoms of demoralization in Lee's army?" General
Meade replied, "No, sir; I saw nothing of that kind."[1]
[Footnote 1: Report of Committee on Conduct of War, Part I., page 337.]
There was indeed no good reason why General Lee should feel any extreme solicitude for the safety of his army, which, after all its losses, still numbered more than fifty thousand troops; and, with that force of veteran combatants, experience told him, he could count upon holding at bay almost any force which the enemy could bring against him. At Chancellorsville, with a less number, he had nearly routed a larger army than General Meade's. If the morale of the men remained unbroken, he had the right to feel secure now; and we have shown that the troops were as full of fight as ever. The exclamations of the ragged infantry, overheard by Colonel Freemantle, expressed the sentiment of the whole army. Recoiling from the fatal charge on Cemetery Hill, and still followed by the terrible fire, they had heart to shout defiantly: "We've not lost confidence in the old man! This day's work won't do him no harm! Uncle Robert will get us into Washington yet—you bet he will!"
Lee's reasons for retiring toward the Potomac were unconnected with the morale of his army. "The difficulty of procuring supplies," he says, "rendered it impossible to continue longer where we were." What he especially needed was ammunition, his supply of which had been nearly exhausted by the three days' fighting, and it was impossible to count upon new supplies of these essential stores now that the enemy were in a condition to interrupt his communications in the direction of Harper's Ferry and Williamsport. The danger to which the army was thus exposed was soon shown not to have been overrated. General Meade promptly sent a force to occupy Harper's Ferry, and a body of his cavalry, hastening across the South Mountain, reached the Potomac near Falling Waters, where they destroyed a pontoon bridge laid there for the passage of the Southern army.
Lee accordingly resolved to retire, and, after remaining in line of battle on Seminary Ridge throughout the evening and night of the 3d and the whole of the 4th, during which time he was busy burying his dead, began to withdraw, by the Fairfield and Chambersburg roads, on the night of this latter day. The movement was deliberate, and without marks of haste, the rear-guard not leaving the vicinity of Gettysburg until the morning of the 5th. Those who looked upon the Southern army at this time can testify that the spirit of the troops was unsubdued. They had been severely checked, but there every thing had ended. Weary, covered with dust, with wounds whose bandages were soaked in blood, the men tramped on in excellent spirits, and were plainly ready to take position at the first word from Lee, and meet any attack of the enemy with a nerve as perfect as when they had advanced.
For the reasons stated by himself, General Meade did not attack. He had secured substantial victory by awaiting Lee's assault on strong ground, and was unwilling now to risk a disaster, such as he had inflicted, by attacking Lee in position. The enthusiasm of the authorities at Washington was not shared by the cool commander of the Federal army. He perfectly well understood the real strength and condition of his adversary, and seems never to have had any intention of striking at him unless a change of circumstances gave him some better prospect of success than he could see at that time.
The retrograde movement of the Southern army now began, Lee's trains retiring by way of Chambersburg, and his infantry over the Fairfield road, in the direction of Hagerstown. General Meade at first moved directly on the track of his enemy. The design of a "stern chase" was, however, speedily abandoned by the Federal commander, who changed the direction of his march and moved southward toward Frederick. When near that point he crossed the South Mountain, went toward Sharpsburg, and on the 12th of July found himself in front of the Southern army near Williamsport, where Lee had formed line of battle to receive his adversary's attack.